Stopping and Range of Ions in Matter
Stopping and Range of Ions in Matter (SRIM) is a group of computer programs which calculate interaction of ions with matter; the core of SRIM is a program Transport of ions in matter (TRIM). The programs were developed by James F. Ziegler and Jochen P. Biersack around 1983 and are being continuously upgraded with the major changes occurring approximately every five years. SRIM is based on a Monte Carlo simulation method, namely the binary collision approximation with a random selection of the impact parameter of the next colliding ion. As the input parameters, it needs the ion type and energy (in the range 10 eV - 2 GeV) and the material of one or several target layers. As the output, it lists or plots
- the three-dimensional distribution of the ions in the solid and its parameters, such as penetration depth, its spread along the ion beam (called straggle) and perpendicular to it, all target atom cascades in the target are followed in detail;
- concentration of vacancies, sputtering rate, ionization, and phonon production in the target material;
- energy partitioning between the nuclear and electron losses, energy deposition rate;
The programs are made so they can be interrupted at any time, and then resumed later. They have a very easy-to-use user interface and built-in default parameters for all ions and materials. Those features made SRIM immensely popular. However, it doesn't take account of the crystal structure nor dynamic composition changes in the material that severely limits its usefulness in some cases. Other approximation of the program include
- binary collision (i.e. the influence of neighboring atoms is neglected);
- recombination of knocked off atoms (interstitials) with the vacancies is neglected;
- The electronic stopping power is an averaging fit to a large number of experiments
- the interatomic potential as a universal form which is an averaging fit to quantum mechanical calculations
- the target atom which reaches the surface can leave the surface (be sputtered) if it has momentum and energy to pass the surface barrier.
- The system is layered, i.e. simulation of materials with composition differences in 2D or 3D is not possible.
- The threshold displacement energy is a step function for each element.
SRIM originated in 1983 as a DOS based program then called TRIM. The DOS version was upgraded until 1998 and is still available for download. It will run on a Unix PC having a DOS emulator. SRIM-2000 requires a computer with any Windows operating system. The program may work with Unix or Macintosh based systems through Wine.[1][2]
References
Further reading
- J. F. Ziegler, J. P. Biersack and U. Littmark (1985 (new edition in 1996)). New York: Pergamon Press.
- J. F. Ziegler and J. P. Biersack and M. D. Ziegler (2008). SRIM - The Stopping and Range of Ions in Matter. SRIM Co.. ISBN 0-9654207-1-X.
- A. Galdikas (2000). Interaction of ions with condensed matter. Nova Publishers. p. 15. ISBN 1560726660.
- J. F. Ziegler (1998). "RBS/ERD simulation problems: Stopping powers, nuclear reactions and detector resolution". Nucl. Instr. Meth. B 136-138: 141. Bibcode 1998NIMPB.136..141Z. doi:10.1016/S0168-583X(97)00664-2.
- J. F. Ziegler (2004). "SRIM-2003". Nucl. Instr. Meth. B 219-220: 1027. Bibcode 2004NIMPB.219.1027Z. doi:10.1016/j.nimb.2004.01.208.
See also
External links